Optical coherence tomography in the diagnosis of Fuchs endothelial corneal dystrophy

Objective. The study evaluated the results of anterior segment optical coherence tomography (OCT) in the diagnosis of Fuchs endothelial corneal dystrophy (FECD). Material and method. The study group included 93 patients, 126 eyes (mean age 70.79±9.69 years), diagnosed with FECD. The control group included 20 patients, 20 eyes (mean age 72.85±6.33 years), without corneal pathology. Eyes in the study group were divided according to the stage of FECD (Volkov—Dronov classification) based on biomicroscopy and corneal endothelial microscopy (EM-4000, Tomey, Japan): stage I (31 eyes), stage II (14 eyes), stage III (65 eyes), stage IV (11 eyes), and stage V (5 eyes). Corneal OCT (RTVue-100, CAM-L, Optovue, USA) in horizontal (B-scan) and En Face (C-scan) modes with construction of 3D images was performed in all cases included in the study. Evaluation of OCT-images involved structural and morphometric analysis of corneal layers. Results. Corneal OCT scans in stage I FECD showed increased optical density of Descemet membrane (DM) and an irregular endothelial contour. Stages II and III were characterized by increased DM thickness (23.00 [21.00; 26.36] and 26.48 [23.60; 29.50] μm, respectively). In stages IV and V, DM had a linear structure, and its thickness corresponded to stage II (20.5 [19.25; 23.00] μm), presumably due to fibrotic changes in the cornea. Progression of FECD (stages II, III, IV, and V) was characterized by increased corneal thickness and pathological involvement of the stroma (striae, lacunae, hyperreflective foci), epithelium (bullae, areas of increased optical density), and damage to Bowman membrane. Conclusion. OCT allows detection of DM changes pathognomonic for FECD and assessment of secondary changes in the stroma, Bowman membrane, and epithelium. The obtained data can be used to determine the disease stage and choose the patient’s treatment strategy.